Matanuska-Susitna Borough

Flood Map Update Project


The Borough joined the National Flood Insurance Program (NFIP)in 1985 with the adoption of the FIRM maps. Since that time a number of flood events as well as substantial population growth have revealed inadequacy of those maps. Development has expanded into areas where the flood risk was not previously studied, leaving folks in harm’s way without any type of warning. Additionally, some of the existing flood zones are flawed, showing risk uphill from the actual area of risk. In 2013, several community meetings were held throughout the Borough and the feedback was clear: the flood maps needed to be updated. The Borough has 3 main watersheds which feed into the area’s rivers, creeks, and streams. Using LiDAR and boots-on-the ground surveys, along with historical flood data, the new maps will more accurately reflect the Base Flood Elevation (BFE) of a given waterway. Knowing how high the water will get, and building above that height, means resident will be safer during a flood event.

Project Benefits

  • Building or elevating a home above the Base Flood Elevation means lower flood insurance premiums for homeowners.
  • Road closures, detour routes, clean-up, and road repairs can be planned.
  • Emergency Services can use this data to plan where to allocate their manpower and resources.
  • Knowing where the watershed drains to and how long it takes for high water to get downstream means advanced warning for communities that will be affected can be issued with greater accuracy.

Project Status

1. High Water Marks: Now Report any high water marks on your property that occurred during any flood event since 1986. This information helps make maps more accurate. Report via e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it. 2. Map Review Period: Coming Soon Once FEMA releases the draft maps, a 90 day public review period will start. Several town hall meetings will be scheduled, along with outreach efforts online and through the mail. It is anticipated that map review will begin in the summer of 2016, although, this date is subject to change.


Mat-Su Floodplain Managers 907-861-7822 This email address is being protected from spambots. You need JavaScript enabled to view it.

Project Docs

risk-map-fact-sheet.pdf (pdf 1.56 MB)   |  399 hits

Project Cost

At this time, the map revision is being provided at
No-Cost to the Borough. The data collected as
part of the LiDAR study completed in 2011 is the
Borough’s contribution to the Risk Map Project.